Production of powdered detergent

ABSTRACT

POWDERED DETERGENT IS PREPARED BY MIXING AN ENZYME OF HYDRASE WITH A NON-IONIC SURFACE ACTIVE AGENT OR A NATURAL OR SYNTHETIC SIZING AGENT AND A DETERGENT BASE HOMOGENEOUSLY.

United States Patent ()1 ice 3,823,090 Patented July 9, 1974 US. Cl. 252-89 2 Claims ABSTRACT OF THE DISCLOSURE Powdered detergent is prepared by mixing an enzyme of hydrase with a non-ionic surface active agent or a natural or synthetic sizing agent and a detergent base homogeneously.

CROSS-RELATED APPLICATION This Application is a continuation of copending Appli cation Ser. No. 738,395 filed June 20, 1968 and now abandoned.

The present invention relates to an enzyme-containing powdered detergent (involving granular and flaky form) and a method of production thereof.

It has been already proposed to form a pre-washing agent to decompose and remove protein and the other stains by compounding an enzyme, such as protease into a detergent, but in the conventional products, finely divided enzyme is mixed with a detergent base (granular, flaky or powdered form) mechanically or the enzyme is conglutinated on the detergent base or builder (granular, flaky or powdered form) by using a non-ionic surface active agent.

However, when the enzyme is mixed with the powdered detergent base by these methods and the resulting detergent is transported or stored for a long period of time, the enzyme or the enzyme composition (hereinafter, meaning an enzyme treated with any process) is not only separated from the detergent base, but also comes into contact with moisture in air or the detergent components to decrease the activity of the enzyme. The degree of lowering of the activity of the enzyme varies depending upon the component constituting the detergent and it is particularly high when using an anionic surface active agent.

The present invention overcomes these difliculties.

An object of the invention is to provide an enzyme containing powdered detergent, which is stable against separation of enzyme and does not lower the activity of enzyme.

Another object of the invention is to provide a method for producing such a powdered detergent.

Such objects may be attained by coating an enzyme with a coating agent as described hereinafter by means of a coating process as mentioned below to prepare an enzyme composition and the resulting composition is mixed with a detergent base.

The coating agent is divided into non-ionic surface active agents having a melting point of 40-1l0 C. and natural and synthetic sizing agents by a general classification.

As the non-ionic surface active agents, mention may be made of (I) Fatty acids having 10 to 24 carbon atoms, for example, single fatty acids, such as, lauric acids, stearic acid, etc., mixed fatty acids obtained from natural oils, such as, coconut oil fatty acids, beef tallow fatty acids, etc.

(II) Fatty alcohols having 16 to 24 carbon atoms, for example, l-octadecanol.

(III) condensates of 1 mole of fatty acids having 10 to 24 carbon atoms with 20 to 60 moles of ethylene oxide, such as, a condensate of stearic acid with ethylene oxide (mole ratio, 1:30).

(IV) Condensates of 1 mole of fatty alcohols having 10 to 24 carbon atoms with 20 to 60 moles of ethylene oxide, such as a condensate of lanolin alcohol with ethylene oxide (mole ratio, 1:60).

(V) Condensates of 1 mole of alkyl phenols having 8 to 18 carbon atom with 35 to 60 moles of ethylene oxide, such as a condensate of nonyl phenol with ethylene oxide (mole ratio, 1:60), a condensate of octyl phenol with ethylene oxide (mole ratio, 1:60).

(VI) Polyalkylene glycol, such as polyethylene glycol having a molecular weight of 1,500 to 30,000, particularly, 4,500 to 9,000, and specifically polyethylene glycol having a molecular weight of 6,000.

(VII) Copolymers of propylene glycol having a molecular weight of less than 2,000 with ethylene oxide, both the ends of the polypropylene glycol being blocked with the ethylene oxide of more than by weight of the copolymer.

(VIII) Condensates of 1 mole of fatty amines having 10 to 24 carbon atoms with 20 to 60 moles of ethylene oxide, such as, a condensate of stearyl amine with ethylene oxide (mole ratio, 1:60) and a condensate of cetyl amine with ethylene oxide (mole ratio, 1:60).

(IX) Amides produced from fatty acids having 8 to 18 carbon atoms and alkylol amine, such as lauryl monoethanol amide.

(X) Esters of polyhydric alcohols with fatty acids or condensates of these esters with ethylene oxide, such as, a condensate of sorbitan monolaurate with ethylene oxide (mole ratio, 1:60).

Of course, these surface active agents may be used in admixture of two or more substances from the above items (I) to (X) or in each item.

Among them, the most preferable coating agent is polyethylene glycol having a molecular weight of 6,000 and the amide produced from a fatty facid and an alkylol amine, such as lauryl monoethanol amide, is desirable.

As the natural and synthetic sizing agents, mention may be made of tragacanth gum, gum arabic, polyvinyl alcohol, polyvinyl acetate, etc. These sizing agents also may be naturally used in admixture of two or more.

In the case when the non-ionic surface active agents are used as the coating agent, such agents are heated and melted at a temperature of 40 to C. and mixed with an enzyme to form a homogeneous fluid, which is subjected to a process, by which the fluid is cooled and cut into flakes or granules, for example, a chilled roller process, a spray process, a floor process and the like, to form an enzyme composition having an apparent specific gravity of 0.1 to 0.8. In this case, the flaky form is most stable against the separation of the enzyme composition from the detergent base after the mixing, so that it is particularly preferable in order to maintain the homogeneous mixture state. Furthermore, the proportion of enzyme occupied in the enzyme composition is 1-95% by weight and more particularly, less than 20% by weight. When this proportion is more than 95% by Weight. the activity of the enzyme lowers.

In the case when the natural or synthetic sizing agent is used as the coating agent, such agent is mixed with an enzyme and water to form a homogeneous fluid mixture, which is subjected to a spray drying process to form a bead state enzyme composition having an apparent specific gravity of 0.1 to 0.8. In this case, the mixture ratio of each component is 20 to 70 parts by weight of the sizing agent, 1 to 50 parts by weight of enzyme and 20 to 70 parts by weight of water.

The reason why the apparent specific gravity of the resulting enzyme composition is 0.1 to 0.8 is as follows:

Namely, if the specific gravity is more than 0.8, when such an enzyme composition is mixed with the detergent, the enzyme composition is liable to be separated from the detergent base in the transportation and it is difficult to maintain the homogeneous mixture.

On the other hand, if the specific gravity is less than 0.1, the enzyme composition is difficult to be mixed with the detergent base.

The term enzyme used herein means hydrolyzing enzymes(hydrase) developing activity at pH of 7 to 12 and a temperature of 10 to 80 C. and includes esterase (broad meaning) to hydrolyze an ester linkage, such as, lipase, esterase (narrow meaning), glucocidase (broad meaning) to decompose glucocide linkage, such as, carbohydrase (decomposing polysaccharides into oligosaccharides), glucocidase (narrow meaning, decomposing oligosaccharides into monosaccharides), peptidase to bydrolyze peptide linkage, such as, Endo-peptidase (cutting peptide chain) and Exopeptidase (decomposing the peptide chain from the end). However, the classification of the peptidase has no distinct definition and peptidase may be called as protease.

The detergent base includes (I) anionic surface active agents, such as, sodium, potassium and ammonium salt of fatty acids, alkylarylsulfonates, alkylsulfates, alkylsulfonates, alkylethoxylated ethersulfates; (II) non-ionic surface active agents, which are substantially non-ionic and surface active in an aqueous solution, such as, condensates of alkyl phenols with ethylene oxide, condensates of fatty acids with ethylene oxide, condensates of fatty alcohols with ethylene oxide, condensates of long chain alkyl amines with ethylene oxide, condensates of fatty acid esters of polyhydric alcohols with ethylene oxide, condensates of alkyl mercaptanes with ethylene oxide and a copolymer of ethylene oxide with propylene oxide; (III) amphoteric surface active agents, such as, dodecyldi(aminoethyl) glycine, which have an anionic group and a cationic group in one molecule and are surface active, as organic detergent components and an inorganic builder, such as, condensated phosphates, silicates, sodium sulphate, borates and an organic builder, such as, carboxymethyl cellulose, benzenesulfonates, ethylenediamine tetraacetate, nitrilo triacetate, etc., some bleaching agents owing to inorganic or organic oxidation and reduction, optical brighteners and the like.

The invention will be further explained in detail by the following Examples. The part and percen mean by weight.

Example 1 Eighty parts of polyethylene glycol having a molecular weight of 6,000 was heated and melted in a mixer at 70 C. and added gradually with 20 parts of Maxatase (made by K.N.G.S. Company in Holland, enzyme activity measured by the following process being 12,500 U./g.) while stirring to form a homogeneous paste, which was formed into flakes having a thickness of 0.5 mm. by means of chilled roller process. The grain distribution in a Tailer sieve was 10% remaining on 10 mesh, 85% passing through 10 mesh and remaining on 32 mesh and passing through 32 mesh. The fraction remaining on mesh was pulverized by a crusher until substantially passing through 10 mesh. The final grain distribution was 1% remaining on 10 mesh, 92% passing through 10 mesh and remaining on 32 mesh and 7% passing through 32 mesh. The apparent specific gravity was 0.48 g./ml. When the resulting product was measured with respect to the activity of enzyme by the following process, all the samples taken up every 30 minutes from the starting of the production to the completion were within the range from 2,475 to 2,505. The mixing time in the mixer was 30 minutes. The time from the starting of pulverization to the completion was 7 hours and the temperature in the mixer was maintained at 70i9 C. Four parts of the resulting enzyme composition was mixed with 96 parts of a detergent base having a water content of 10% and an apparent specific gravity of 0.27 and a grain distribution of passing through 10 mesh and remaining on 48 mesh, which was obtained by spraying and drying a mixture having the composition as shown in the following Table 1, to obtain a detergent (I).

Table 1 Composition of detergent base (sold content) Component: Mixture ratio (percent) Sodium dodecylbenzene sulfonate 30 Sodium tripolyphosphate 25 Carboxymethyl cellulose 5 Sodium silicate 10 Sodium sulfate 29.5

Stilikene type optical brightener 0.5

Total 100 .0

500 g. of the resulting detergent was introduced into a plurality of cartons which were kept in a thermohumidistat at a temperature of 40 C. and a relative humidity of 85 for two months and the variation of the activity of the enzyme was measured by the following process for measuring the activity of the enzyme.

A process for measuring the activity of enzyme:

1.5 g. of milk casein (made by MERK, for Biochemistry) was dissolved in 30 ml. of 0.1 N aqueous solution of sodium hydroxide and added with 30 ml. of pH 10 of a buffer solution and water so as to make 100 ml. 1.0 ml. of the resulting solution was introduced into a test tube and heated to 40 C. and added with 1 m1. of a solution of enzyme to be tested and maintained at 40 C. for 60 minutes. The resulting mixture was added with 2 ml. of 0.4 mol/l. aqueous trichloroacetic acid solution and the reaction was stopped and further the mixture was left to stand at 40 C. for 25 minutes and then filtered. 1.0 ml. of the filtrate was introduced in a test tube and added with 5 ml. of 0.4 mol/l. aqueous sodium carbonate solution and 1 ml. of 5 times diluted solution of Folin reagent and maintained at 40 C. for 20 minutes to develop color and measured the optical density (1B) of 660 m, by means of 10 mm. cell. Separately, water was operated in the same manner as described above and the optical density (E) is measured. The activity unit of enzyme (A) was calculated from the following formula:

A= (E E') m1. of the diluted solution (unit is tug.)

gram of the sample For a comparison, 0.8 part of Maxatase as described above was mixed with 99.2 parts of the same detergent base as described above mechanically to make a control detergent (HI) and the enzyme activity of this detergent is the same as that of the above detergent (I).

The results are shown in the following Table 2 and as seen from this Table, the detergent (I) retains the activity of enzyme for a longer period of the time than the detergent (111).

The following Table 3 shows the results obtained by measuring the variation of the activity of the enzyme in the above described process, when both the detergents were left to stand in the natural state for one year, and as seen from this Table, the detergent (I) retains the activity of the enzyme for a longer period of time than the detergent (III).

Then, in order to determine the degree of separation of the enzyme composition from the detergent base, the above detergents (2.6 kg.) were shaken thoroughly and loaded on a truck and transported about 2,000 km. From the upper layer and the lower layer of the carton, 20 g. was sampled and the activity of the enzyme was measured and the results are shown in the following Table 4. As seen from the Table 4, the detergent (I) is less in degree of separation than the detergent (III).

Example 2 Forty parts of gum arabic, parts of Maxatase and 50 parts of water were mixed at 20 C. and the mixed solution was sprayed and dried in a co-current spraydrying tower with an introducing temperature of hot air being 150 C. and an exhausting temperature being 85 C. under normal pressure to form an enzyme composition composed of a mixture of hollow granules and needles and the grain distribution was 3% remaining on 20 mesh, 62% passing through 20 mesh and remaining on 48 mesh, 28% passing through 48 mesh and remaining on 70 mesh and 7% passing through 70 mesh and the apparent specific gravity was 0.32 g./ml. The activity of the enzyme of this composition was 2,280 U./g.

and the water content was 1.5%. 4.4 parts of the enzyme composition was mixed wth 9516 parts of the same detergent base as described in Example 1 to form a detergent (II).

In the cases when the detergent (II) was stored in the same manner as described in Example 1 at a temperature of 40 C. and a relative humidity of 85% for two months and when the detergent was left to stand in natural state in a chamber for one year, the variation of the activity of enzyme was determined and the results are shown in the following Tables 2 and 3. As seen from these Tables 2 and 3, the detergent (H) retains the activity of the enzyme for a longer perod of time than the detergent (III). In the same manner as described in Example 1, the degree of separation of the enzyme composition from the detergent base was determined and the results are shown in the following Table 4. As seen from this Table, the detergent (II) is lower in the degree of separation than the detergent (III).

TAB LE 3 At 10 a.m.

Detergent Average Average (1) (II) (III) temp. h dity 5 lAntitmediately alter mixing. 100 98 101 98 75 24 65 96 24 28 72 92 16 31 75 88 13 27 72 10 85 10 23 68 80 10 19 68 81 8 62 78 5 10 66 78 4 12 62 76 4 16 68 77 3 17 72 15 76 4 22 74 Norm-The numeral value is average of 5 samples.

TABLE 4,-SEPARATION TEST Detergent (I) (II) (III) Immediately after mixing homogeneously 102 101 100 After transportation:

Upper layer 99 101 51 Lower layer 100 147 25 Example 3 parts of coconut oil fatty acid monoethanol amide were heated and melted at 80 C. and mixed with 20 parts of protease (Trade Name, Maxatase, made by K.N.G.S. Co. in Holland) to form a homogeneous paste, which was cooled and cut into flakes and then the flakes were pulverized until they passed through 10 mesh of a Tailer sieve.

Example 4 The enzyme composition was prepared in the same mannor as described in Example 3, except that a condensate of 1 mole of nonyl phenol with 60 moles of ethylene oxide was used instead of coconut oil fatty acid monoethanol amide.

Example 5 A detergent base having a composition as shown in the following Table 5 was added with the enzyme compositions obtained in the above Examples 3 and 4 so as to provide 100 units of enzyme activity and the resulting powdered detergents were kept in a thermohumidistat at a tem- 'perature of 40 C. and a relative humidity of and the variation of enzyme activity was determined to obtain the results as shown in the following Table 6.

As seen from the above table, the powdered detergents of the invention are superior in storage stability to .the

control sample. The blank was prepared by mixing only Maxatase with the detergent base so as to be about units of enzyme activity.

What is claimed is: g

1. A method of producing a powder detergent composition comprising mixing protease with polyethylene glycol having a molecular weight of 6000 to form a fluid mixture, the protease being present in an amount between 1 and 95% by weight, cooling the fluid mixture to form coated solid particles of protease, and mixing the thus coated particles with a detergent base containing an anionic surface active agent.

2. A method as claimed in claim 1 wherein the amount of protease is less than 20% by weight of the mixture;

References j Cited UNITED STATES PATENTS Feierstein et a1. 195-63 X FOREIGN :PATENTS 3/1963; Canada.

5/ 1922 France.

11/ 1967 South Africa.

D. Primary Examiner P. E.=WILL IS, Assistant Examiner 7 

